Title :
A varactor-tuned, active microwave band-pass filter
Author :
Chang, C.-Y. ; Itoh, T.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
Abstract :
A microwave tunable high-Q active bandpass filter was developed using a varactor diode for tuning and a MESFET to provide negative resistance for increasing the tank circuit Q-value. Tuning ranges of 500 MHz for the one-pole filter and 430 MHz for the two-pole filter were achieved with a center frequency of 10 GHz. A 3-dB bandwidth of 20 MHz for the one-pole filter and 80 MHz for the two-pole filter was obtained. The passband insertion loss is typically 0+or-1 dB.<>
Keywords :
Q-factor; Schottky gate field effect transistors; active filters; band-pass filters; microwave filters; solid-state microwave circuits; strip line components; tuning; varactors; 10 GHz; 20 MHz; 80 MHz; MESFET; SHF; active bandpass filter; high-Q; microstrip circuit; microwave band-pass filter; negative resistance; one-pole filter; tank circuit; two-pole filter; varactor diode; varactor-tuned; Band pass filters; Circuit optimization; Diodes; Frequency; MESFET circuits; Microwave circuits; Microwave filters; Tunable circuits and devices; Tuning; Varactors;
Conference_Titel :
Microwave Symposium Digest, 1990., IEEE MTT-S International
Conference_Location :
Dallas, TX
DOI :
10.1109/MWSYM.1990.99628
